Polyvinyl chloride composition having as polymerizable plasticizer a mixture of alkylene dimethacrylate and an alkyl methacrylate of 6 to 18 carbon atoms



comprising halogen-containing vinyl resins.

United States Patent ()fiice 3,247,289 Patented Apr. 19, 1966 This invention relates to new and useful compositions More particularly this invention is concerned with compositions comprising halogen-containing vinyl resins and a plasticizer, the latter comprising an alkylene dimethacrylate and an alkyl methacrylate. The invention has special utility with respect to the production of halogen-containing vinyl resin plastisols, organosols, and dry blends wherein the alkylene dimethacrylate-alkyl methacrylate plasticizer functions efiectively as a polymerizable plasticizer which in turn yields a plasticized resinous composition characterized by a permanence of plasticization.

Normally, vinyl halide polymers such as polyvinyl chloride and copolyrners thereof, which are widely employed in the plastics industry, are quite hard and brittle in nature and require the addtion of substantial proportions of a plasticizer to improve their workability. It is desirable to use a plasticizer which does not permit the product to become hard and brittle and thus easily fractured. It

is especially desirable to use a plasticizer which will impart essentially permanent semi-rigid properties to the polymer composition, thereby eliminating the probability of the plasticizer being extracted and leaving the product brittle again.

It is an object of this invention to provide improved halogen-containing vinyl resin compositions.

Other objects and advantages of this invention will become apparent from the following description of the invention.

In accordance with this invention, it has been found that a plastisol comprising a halogen-containing vinyl resin and a polymerizable plasticizer, the latter comprising an alkylene dimethacrylate andan alkyl methacrylate, may be fused and cured to a semi-rigid material whose physical properties are esesntially permanent. The aforementioned plastisols are prepared in a well-known manner by intimately mixing or stirring a finely divided resin with a novel polymerizable plasticizer, preferably in conjunction with a small amount of a peroxy polymerization catalyst, until a smooth dispersion is obtained. This composition, upon molding and curing, results in a flexible material exhibiting essentially permanent physical prop' erties.

The halogen-containing resins of thisinvention are those;

Illustrative are the such materials as vinylidene chloride; vinyl esters of carboxylic acids, e.g. vinyl acetate, vinyl propionate, vinyl butyrate, vinyl benzoate; esters of unsaturated acids, e.g. alkyl acrylates such as methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, allyl acrylate, and the corresponding esters of methacrylic acid; vinyl aromatic compounds, e.g. styrene, ortho-chlorostyrene, para-chlorostyrene, 2,5-dichlorostyrene, 2,4-dichlor0styrene, paraethyl styrene, vinyl naphthalene, wrnethyl styrene; dienes "such as butadine, chlorobutadiene; unsaturated amides suchasacrylic acid amide, acrylic acid anilide; unsaturated nitriles such as acrylic acid nitrile; esters of afiunsaturated carboxylic acids, e.g. the methyl, ethyl, propyl, butyl, amyl, hexyl, heptyl, octyl, allyl, methallyl and phenyl esters of maleic, crotonic, itaconic and fumaric acids and the like.

- It should be recognized that halogenated resin-s containing halogen atoms other than chlorine e.g. bromine, fluorine and iodine, are also operable in this invention. Said resins may contain varying proportions of halogen depending upon the nature of the resin and its contemplated use.

Those copolyrners in which a predominant portion, i.e., at least 50% by weight of the copolymer is made from a halogen-containing vinyl compound such as vinyl chloride represent a preferred class of polymers to be treated according to this invention.

The above halogen-containing vinyl resins are of the dispersion type, and their preparation is well-known in the art. They are usually prepared by a conventional aqueous emulsion polymerization which produces a latexlike dispersion of the halogen-containing resin. The polymeric material is recovered from the latex-like dispersion by a'coagulation or flocculation process as a fine powder wherein usually 95% of the particles are within iCLOSmicron of the mean particle size. Halogencontaining dispersion type resins having a wide range of average particle size, as for example, from about 0.05 to about 200 microns, can be employed in practicing this invention. However, the use of powdery halogen-com taining resins having an average particle size of from 0.05 to about 30 microns is preferred. Powdery dispersion type resins having a particle size less than 0.05 micron may tend to dissolve too readily in the plasticizer and cause the plastisol to gel. Powdery dispersion resins having an average particle size greater than about 30 microns may tend to form grainy plastisols.

The alkylene dimethacrylates useful in the composipractice of this invention are alkylene glycols, as for example, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 2-n1ethyl-2-ethyl-1,3-propanediol, 1,2-butanediol, 1,3 .butaned-iol, 1,4.-butanediol, 2-butene-1,4-diol, 2,3- butanediol, 2,2.-dimethylpropane-1,3 -diol,, 1,4-pentanediol, 1,5-pentanediol, 1,6,-hexanediol, 2-methyl- 2,4-pentanediol, 2,3-dimethyl 2,Lbutanediol, 2,2-diethyl- 1,3-prop'anediol, 1,1-0-decanediol, 1-,12-octadecanediol, 9,10-octadecanediol", and the like; polyalkylene glycols such vas diethylene glycol, triethylene glycol, tetraethylene glycol,

3 pentaethylene glycol, hexaethylene glycol, dipropylene glycol, tripropylene' glycol and the like. I

The term alkyl methacrylate as used herein is mean to include monomers of alkyl methacrylates in which that compositions containing such other additives are within'the scope of this invention.

A particularly valuable property of the plasticized vinyl halide compositions which are prepared in accordance the alkyl group contains from six to eighteen-carbon 5 with the present invention is the permanence of plastiatoms. As illustrative of the alkyl methacrylates concization. As a result of such permanence the compositemplated by this invention are hexyl methacrylate, sec.- tions of this invention tend to remain free from embrittlehexyl methacrylate, 2,2-dimethyl-3-butyl methacrylate, ment with the passage of time. The use of such polym- 2,2-dimethyl-4-butyl methacrylate, 2,3-dirn'ethyl-2-butyl erizableplasticizers eliminates necessity of maintaining methacrylate, Z-methyl-lpenytl methacrylate, Z-methylthe wide tolerance in physic'al'dimensions of castings and 2-penty1 methacrylate, 3-rnethyl-1-phenyl methacrylate, moldings which are required when non-polymerizing plasetc., heptyl methacrylate, sec.heptyl methacrylate, 2,3- ticizers are employed. dimethyl-3-pentyl methacrylate, 2,4 dimethyl-Z-pentyl According to the present invention, novel resinous commethacrylate, 2,4-dimethyl-3-pentyl methacrylate, 2,2,3- positions are prepared by stirring together, in the weight trimethyl-B-butyl methacrylate, 3-ethyl-2-pentyl methproportions set forth below, a dispersion type halogen- ..acrylate, 2-methyl-2-hexyl methacrylate; --octyl methcontaining resin, an alkylene dimethacrylate and an alkyl acrylate, 2-ethylhexyl methacrylate, nonyl, methacrylate, methacrylate. From the resulting composition films or decyl methacrylate, lauryl methacrylate, myristyl methshaped articles are formed by casting, molding, extrud acrylate, cetyl methacrylate, stearyl methacrylate and the ing, calendaring, coating or by other known methods. like. Alkyl methacrylates in which the alkyl groups con- Such films or articles are then converted to the cured .tain from twelve to eighteen carbon atoms represent an state by heating at from about 150 C. to about 170 especially preferred class of methacrylatesto be used C. for about 5 to about minutes. The cured matein this invention. rial is cooled to room temperature.

The alkyl methacrylates and methods for their prepa- In order to facilitate the curing of the polymerizable ration are well-known to the art. The alkyl methacrylates 25 .plasticize-r in the resin dispersion within a practicable are usually prepared by the alcoholysis of methyl methtime period, it is preferred to incorporate from 0.5% to acryl-ate. about 5% by Weight of a polymerization catalyst, based Generally speaking, about 10 to 400 parts by weight on the weight of the polymerizable plasticizer. While of a plasticizer mixture, as hereinafter described, can be any of the peroxy polymerization catalysts such as benused for each 100 parts by weight of resin. However, it zoyl peroxide, acetyl peroxide, succinyl peroxide, methyl is particularly preferred to use from about 30 to 80 parts ethyl ketone peroxide, cumene hydroperoxide, tertiaryby weight of plasticizer per 100 parts by Weight of resin. butyl hydroperoxide, perbenzoic acid, peracetic acid, ani- Each 100 parts by weight of said plasticizer can be soyl peroxide, tolyl peroxide, p-bromobenzoyl peroxide, comprised of from about 10 to about 90 parts by weight furoyl peroxide, chloracetyl peroxide are effective, it is .of an alkylene dimethacrylate and from about 10 to preferred to use t-butyl perbenzoate or benzoyl peroxabout 90 parts by Weight of an alkyl methacrylate Whereide. Other catalysts Well adapted for use in this invenin the ratio of alkylene dimethacrylate to alkyl meth- .tion include the aliphatic azo catalysts such as alpha, acrylate is at least about 1:10. In preferred formulaalpha azo-diisobutyronitrile and alpha, alpha azo-bistions, each 100 parts by Weight of the plasticizer comalpha, gamma-dimethyl valeronitrile. prises from about 50 to about 80 parts by weight of al- The invention will be more fully understood by referkylene dimethacrylate and from about 20 to about 50 ence to the following examples. These examples, howparts by weight of an alkyl methacrylate wherein the ever, are given for the purpose of illustration only and ratio of the alkylene dimethacrylate to the alkyl methare not to be construed as limiting the scope of the ,acrylate is at least about 1:1. present invention in any way.

For many purposes it may be desirable to blend other Resinous compositions are prepared by stir-ring together, conventional additives with the plasticized vinyl halide in the weight proportions set forth in Table I, a disperpolymer compositions of the present invention. Illussion type polyvinyl chloride resin and the plasticizer. trative of such additives are fillers, dyes, pigments, sta- The properties of the resulting compositions after fusion bilizers, lubricants, and the like, and it will be apparent are given in Table II.

Table I Parts by weight ABODEFGHIJKLMNOPQRSTUVWXY Diethylene glycol dimethacrylate 50 60 70 80 90 50 60 70 80 90 50 60 70 so 90 50 60 70 so 90 Laurylmethacrylate- 50 40 30 20 10 50 40 30 20 10 50 40 30 20 10 stearyl methacrylate 50 40 30 20 10 50 40 30 20 10 Polyvinyl chl0ride -233 233 233 233 233 150 150 150 150 25 25 25 25 25 233 253 233 235 233 150 150 150 150 150 Table II ABGDEFGHIJKLMNOPQRSTUVWX'Y Elongation, percent 26 16 10 s 6 22 16 10 s 6 1s 16 10 8 6 36 56 58 30 6 26 3s 1s 10 6 Yieldpoint,1,G00p.s.i 4.5 5.5 6.0 6.5 6.75 2.7 4.25 5.0 5.75 6.5 0 1.8 3.25 4.0 4.6 3.0 3.4 4.0 4.5 5.0 2.8 3.4 4.4 5.9 7.0

Noun-The tensile properties set forth above were determined on dumbell specimens having the neck 0.475 inch long and 0.118 inch wide using an Instron tensile tester model TTC.

As illustrative of the prior art, compositions and physical properties of cured resins prepared with a plasticizer mixture consisting of a non-polymerizable plasticizer and Further examples of compositions of this invention exhibiting similar results as obtained by the use of compositions of Table I are shown in Table V.

Table V Parts by weight Dipropylene glycol dimethacrylate 1,4-butanediol dimethracrylate 1,6-hexanediol dimethracrylate Lauryl methacrylate Stearyl methacrylate Polyvinyl chloride Copolymer of 90 parts nyl ehlor e and 10 parts vinyl acetate Copolymer of 90 parts vinyl chloride and 10 parts vinylidene chloride Copolymer of 90 parts vinyl chloride and 10 parts diethyl maleate an alkylene dimethacrylate, are shown in Tables III and IV.

Norm-The tensile properties set forth above were determined on dumbell specimens having the neck 0.475 inches long and 0.118 inches wide using an Instron tensile tester model TTC.

Compositions F, G, H, I, J, U, V, W, X, and Y (Tables I and II) containing polymerizable plasticizer mixtures of this invention show small variance in elongation and tensile strength. In comparison, Wide variance of such properties are obtained with compositions 1, 2, 3, 4 and 5 (Tables III and IV) wherein a conventional non-polymerizable plasticizer is part of the plasticizer mixture.

From the foregoing :results it is evident that the compositions of this invention have improved physical properties over compositions prepared with a conventional plasticizer. The results also indicate that variations in the percentage of plasticizer in the compositions of this invention are not as critical as are similar variations when using conventional nonpolymerizable plasticizers as shown in Tables III and IV. Similar physical properties are obtained in the compositions of this invention, even over a Wide range of plasticizer concentrations, Whereas compositions containing conventional plasticizers exhibit a shift in physical properties with small changes in the plasticizer concentration.

Although this invention is directed primarily to plastisol compositions, it is equally applicable to organosol and dry blend formulations.

A typical organosol composition of this invention consists of 280 parts by weight of polyvinyl chloride, 95 parts by weight of diethylene glycol dimethacrylate, 23 parts by weight of lauryl methacrylate and 2 parts by weight of hexane.

Exemplary of a dry blend formulation is 60 parts by weight of polyvinyl chloride, 24 parts by weight of diethylene glycol dimethacrylate, and 16 parts by weight of lauryl methacrylate.

While this invention has been described with respect to certain embodiments, it is not so limited and it is to be understood that variations and modifications thereof may be made which are obvious to those skilled in the art without departing from the spirit or scope of this invention.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A composition consisting essentially of (a) apolymer of vinyl halide selected from the group consisting of homopolymers of vinyl halide and copolymers of vinyl halide containing at least 50% vinyl halide and up to 50% of an ethylenically unsaturated monomer copolymerizable therewith, (b) an alkylene dimethacrylate having a molecular weight up to about 600, and (c) an alkyl methacrylate in which the alkyl radical contains from 6 to 18 carbon atoms.

2. A composition as defined in claim 1 consisting essentially of from about 10 to about 400 parts by Weight of a mixture of (b) and (0) per 100 parts by weight of (a) and wherein the weight ratio of (b):(c) is at least about 1:10.

3. A composition as defined in claim 1 consisting essentially of from about 30 to about parts by weight of a mixture of (b) and (0) per parts by Weight of (a) and wherein the weight ratio of (b):(c) is at least about 1:1.

4. A composition as defined in claim 2 wherein the vinyl halide polymer is .a homopolymer.

5. A composition as defined in claim 2 wherein the vinyl halide polymer is a vinyl chloride polymer containing at least 50% vinyl chloride.

6. A composition as defined in claim 2 wherein the vinyl halide polymer is a copolymer of vinyl chloride and vinyl acetate.

7. A composition consisting essentially of (a) polymerized vinyl chloride, (b) an alkylene dimethacrylate having a molecular weight from about to about 350 and (c) an alkyl methacrylatc in which the flkyl radical contains from 12 to 18 carbon atoms. 7

8. A composition as defined in claim 7 consisting essentially of from about 10 to about 400 parts by weight of a mixture of (b) and (c) per 100 parts by weight of (a) and wherein the weight ratio of (b):(c) is at least about 1:10.

9. A composition as defined in claim 8 wherein the alkylene dimethacrylate is diethyl-ene glycol dimethacrylate.

10. A composition as defined in claim 8 wherein the alkyl methacrylate is lauryl methacrylate.

11. A composition as defined in claim 8 wherein the alkyl methacrylate is stearyl methacrylate.

12. A composition as defined in claim 8 wherein the alkylene dimethacrylate is dipropylene glycol dimethacryof (a) and wherein the weight ratio of (b):(c) is at 1east about 1:1.

14. A composition consisting essentially of from about 30 to about 80 parts by weight of a mixture of diethylene glycol dimethacrylate and lauryl methacrylate per 100 parts by weight of polymerized vinyl chloride and where in the weight ratio of diethylene glycol dimethacrylate to lauryl methacrylate is at least about 1:1.

References Cited by the Examiner UNITED STATES PATENTS Strain 1260-895 Marks 26089.5 Brophy et a1. 260891 .Burt 260884 Cooper 260884 Leese 260884 Examiners. 

1. A COMPOSITION CONSISTING ESSENTIALLY OF (A) A POLYMER OF VINYL HALIDE SELECTED FROM THE GROUP CONSISTING OF HOMOPOLYMERS OF VINYL HALIDE AND COPOLYMERS OF VINYL HALIDE CONTAINING AT LEAST 50% VINYL HALIDE AND UP TO 50% OF AN ETHYLENICALLY UNSATURATED MONOMER COPOLYMERIZABLE THEREWITH, (B) AN ALKYLENE DIMETHACRYLATE HAVING A MOLECULAR WEIGHT UP TO ABOUT 600, ADN (C) AN ALKYL METHACRYLATE IN WHICH THE ALKYL RADICAL CONTAINS FROM 6 TO 18 CARBON ATOMS. 